Wax decomposition inhibitor



Patented June 9, 1942 STATES FATE T H. Latham, Wilmingto 11, Del.,asslgnors to Remington Arms Company, Inc., a corporation of Delaware NoDrawing. Application June 26, 1940,

Serial No. 342,442

11 Claims.

This invention relates to means to prevent the decomposition of hot wax.More particularly, it relates to an inhibitor to be used in a hot waxbath, said bath being kept at an elevated temperature for processpurposes. As an example of the use of the present invention, paper shotshell tubes may be impregnated with a paraffin wax in such a bath. Thewax bath into which the paper tubes are dipped for impregnation is keptat a temperature of between 230 and 240 F. (l-115.5 0.), so that the waxis liquid and will readily penetrate the paper. The elevated temperatureis necessary to secure the proper penetration of the wax in the paper.When a wax, such as a parafiin wax, is kept at this tem- Y perature in atank for an extended period, acidic The degree of the decomposition canbe measured by determining the saponification value of the wax. Thisdecomposition also results in loss of a large amount of wax and causes aloss of time in the reclaiming and correction of the condition of thedecomposed wax. This loss of wax may be attributed to the volatilizationof the volatile decomposition products, to the discarding of the entirelot of the wax being used or to the discarding of the sweatings afterpurifying the decomposed wax. Another difiiculty that is prevented bythe use of the inhibitor of this in vention is the lowering of themelting point of the wax by the decomposition. When no inhibitor isused, oily decomposition products accumulate in the wax which lower themelting oint. This is of particular importance in shot shell tubesbecause the lower melting point will allow the wax to migrate into thepowder of the shot shell, at a lower temperature, thereby materiallyaffecting and decreasing the efliciency of the powder. It is possiblethat this is a matter of surface tension. Previously, it was necessaryto replace part of the old wax with a fresh wax at sufiiciently frequentintervals to prevent the saponification value from going above, forexample, 10 or 12, whereas with the inhibitor of the present inventionit is possible to use the "elevated temperatures.

same wax for a considerable length of time. It has been found desirablein general to keep the saponification value below 10 or 12, although itis to be understood that it is not limited thereto. The saponificationvalue may be determined by any standard method such as that disclosed onpage 388 of Chemical Technology and Analysis of Oils, Fats and Waxes byLewkowitsch (6th ed., vol. I). Many materials have been tried for thepurpose of preventing the decomposition of the wax, but most of thesewere found to be unstable at the temperature used, thereby giving a darkbrown or black color, or resulting in a sludge formation. Somesubstances used also showed a tendency to cause-tarnishing of the brassshot shell head and to develop a foul odor in the wax. It has been foundthat by the use of poly-alkylated phenol. and especially polymethylphenol, that the decomposition of the wax bath is inhibited. In thecatalytic synthesis of methanol from carbon monoxide and hydrogen, amixture of poly-alkylated phenols is produced. These are producible bythe high pressure catalytic hydrogenation of carbon monoxide andinclude, among other things, 2-6 dimethyl and 2-4-6 trimethyl phenol. Itis also possible to redistill this mixture of poly-alkylated phenols anduse the redistilled product as the inhibitor.

It has been found that as low as 2% of the inhibitor may be added to thewax bath to give goodresults.

The following table is a summary of results obtained with the inhibitorof this invention in a crude scale paranin wax, in comparison with theuntreated wax:

- Saponilication value Amount of mixture of poly-alkylated phenols;percent of wax 72 hours 141 hours 2301101115 It is to be understood thatthe example given of the impregnation of paper shot shell bodies in thewax bath is merely for purposes of illustration and that the hot waxbath may be employed for other uses, such as, for example, other waximpregnated paper articles or any other place where a wax bath must bemaintained at By this invention a method of preventing a bothersome andexpensive decomposition of a hot wax bath has been devised. As manydifierent embodiments of this 3. The method of inhibiting thedecomposition of a hot wax bath comprising adding thereto a 2-4-6trimethyl phenol.

4. The method of inhibiting the decomposition of a hot wax bathcomprising adding thereto a mixture including 2-6 dimethyl phenol and2-4-6 trimethyl phenol.

5. The method of inhibiting the decomposition oi a hot wax bathcomprising adding thereto at least 2% of poly-methylated phenols.

6. The method of inhibiting the decomposition of a hot wax bathcomprising adding thereto at least 2% of a mixture including 2-6dimethyl phenol and 2-4-6 trimethyl phenol. v

7. The method of inhibiting the decomposition of a, molten parafin waxbath maintained at an elevated temperature of about 230 to 240 F.(ll@-1l5.5 C), which comprises incorporating therein at least 0.2% ofthe mixture of 2:6-dimethyl phenol and 2:4:6-trimethyl phenol.

8. The process of impregnating with paramn wax the paper tubes of shotshells, while preventing the formation therein of materials which maycause migration of the impregnating material from the paper tubes to thepowder in loaded shot shells, and which may also tarnish the brass headsof said shells which comprises immersing the paper tube in a hot paramnwax bath to which has been added at least 0.2% of its weight ofpolymethylated phenol material maintained at a temperature of 230-240 F.(110-115.5 C.) until the paper is impregnated with the bath material.

9. The process of impregnating with paraflin wax the paper tubes of shotshells, while preventing the formation therein of materials which maycause migration of the impregnating material irom the paper tubes to thepowder in loaded shot shells, and which may also tarnish the brass headsof said shells which comprises immersing the paper tube in a hotparaflin wax bath in which has been incorporated at least 0.2% of itsweight of a 2:4:6-trimethyl phenol-2:6-dimethyl phenol mixturemaintained at a temperature of 230-240 F. (110-115.5 C.) until the paperis impregnated with the bath material.

10. The process of impregnating with paraflin wax the paper tubes ofshot shells, while preventing the formation therein of materials whichmay cause migration of the impregnating material from the paper tubes tothe powder in loaded shot shells, and which may also tarnish the brassheads of said shells which comprises immersing the paper tube in a hotparaflin wax bath in which has been incorporated at least 0.2% of itsweight of 2:4:6-trimethyl phenol maintained at a temperature of 230-240F. (-115.5 C.) until the paper is impregnated with the bath material.

11. The method of impregnating paper shot shells with wax, whichcomprises dipping the paper shot shells into a wax bath comprisingessentially molten paraflin wax and at least 0.2% of polymethylatedphenol.

ALBERT A. SCHILLING. GEORGE H. LATHAM.

